Electric heating apparatus



July 27, 1965 J. WETLES EN ELECTRIC HEATING APPARATUS 2 Sheets-Sheet 1Filed March 20, 1961 'II'IIIIIIIIIIIIII'II' y 1965 J. WETLESEN 3,197,615

ELECTRIC HEATING APPARATUS Filed March 20, 1961 2 Sheets-Sheet 2 Pics.4.

INV EN TOR. JOHAN WETLESEN WW w v A TTOAN'E United States Patent3,197,615 ELECTRIC HEATING APPARATUS Johan Wetlesen, Toronto, Ontario,Canada, assiguor to Edwin L. Wiegand Company, Pittsburgh, Pa. Filed Mar.20, 1961, Ser. No. 97,695 4 Claims. (Cl. 219-404) The present inventionrelates to electric heating apparatus, more particularly to suchapparatus for use with an oven of an electric range, and the principalobject of the invention is to provide new and improved apparatus of suchcharacter.

It has long been common to provide ovens of electric ranges with abaking element and, in most instances with a broiling element. Theformer element is usually positioned adjacent the bottom wall, or floor,of the oven while the latter element is usually positioned adjacent thetop wall, or root of the oven. Because of the close spacing of theelements aforesaid with their respective walls, it is consideredessential that the elements be shiftable away from such walls tofacilitate cleaning of the latter.

Two expedients are commonly used to provide for the aforesaid shiftingof these elements. In the first, one wall of the oven, usually the rearwall, provides sockets into which respective elements may be plugged.Thus, the elements are bodily removable from the oven when the latter isto be cleaned. In the second, the elements are pivoted to one of theoven walls, usually the rear wall, so that the elements can be pivotedaway from their respective adjoining walls, when the latter are to becleaned. While the first type of construction is satisfactory in thatcleaning of the oven is no problem, such constructions has beenexpensive initially and were troublesome to install and maintain.Accordingly, the second type of construction has come into even widerusage.

The present invention is concerned with the above mentioned second typeof construction and has as its principal objects the provision of astructure which is low in cost, quickly installed, trouble-free inoperation and highly efiicient in use. Other advantages will readilybecome apparent from a study of the following description and from thedrawings appended hereto.

In the drawings accompanying this specification and forming a part ofthis application there is shown, for purpose of illustration, anembodiment which the invention may assume, and in these drawings:

FIGURE 1 is a fragmentary perspective view of an electric heaterassembly of the present invention in operable relation with the oven ofan electric range,

FIGURE 2 is an enlarged, fragmentary sectional view generallycorresponding to the line 22 of FIGURE 1,

FIGURE 3 is a reduced size, exploded, fragmentary perspective view ofparts seen in FIGURES l and 2, and

FIGURE 4 is a view similar to FIGURE 2 but with certain parts shown inanother position.

With reference to FIGURE 1, there is fragmentarily shown an oven of anelectric range having a bottom wall 10, a top wall 11, side walls 12,and a rear wall 13. Although not shown, the front of the oven will beclosed by the usual door which provides access to the oven interior.Disposed Within the oven is an electric heating element 14 of the usualtype wherein a resistor conductor is disposed within an intermediateportion of an elongated tubular sheath which is filled with compacted,heat-conductive, electric-insulating material. Connected to respectiveends of the conductor within the sheath are the usual terminal pins 15(see FIGURES 2 and 3) which project beyond respective sheath ends forconnec tion to a suitable source of electrical energy. The intermediateportion of the heater, that portion in which is enclosed the resistorconductor, is often referred to as 3.,lh7fii5 Patented July 2?, 1965 theheat-generating portion of the element while its end portions, whichenclose the terminal pins 15, are often referred to as the terminalportion of the heater.

In the present embodiment, the intermediate portion 16 of the element isbent to a rectangular configuration generally corresponding to that ofthe bottom wall of the oven and its terminal ends 17 are broughttogether in spaced, side-by-side relation for projection through therear wall 13 of the oven, as will later appear. Thus, the element 14 hasits heat-generating portion disposed on one side of the wall 13 withinthe chamber provided by the oven walls while the terminal portion of theelement is disposed on the other side of the wall 13 (see FIGURE 2) onthe outside of the oven chamber.

With reference to FIGURES 2 and 3, the rear oven wall 13 is presentlyformed with a rectangular opening 18 adjacent the oven bottom wall Illthrough which project the element ends 17. Extending between the elementends 17 is a plate 19 which provides a radially extending flange. Anysuitable means may be employed to rigidly secure this plate to theelement and in the present embodiment, the plate has extruded aperturesthrough which the element ends 17 extend. Such apertures providecircumscribing collars 20 which are tightly crirnped about respectiveelement ends 17. Obviously, the plate could be welded or brazed to theelement to form the desired structural rigidity therebetween. It is tobe noted that plate 19 is smaller than the wall opening 13 so as tofreely pass therethrough.

Means are provided for shiftably securing the element to the oven wall13 and, in the present embodiment, such means preferably comprises asheet metal plate 21 of considerable flexibility. At the present time,plate 21 is formed of thin, spring-like material and is of a size largerthan the wall opening 18 so as to overlie and close the latter (seeFIGURE 2).

For a purpose to appear, oversized apertures 22 in the plate 21 passrespective element ends 17 and, in the position of parts shown, theupper margin of plate 21 is removably secured to the inside of the ovenwall by means of sheet-metal screws 23, or the like, which pass throughaligned apertures 24 in plate 21 and apertures 25 in the oven wall 13.It is to be understood that in the normal position of parts seen inFIGURE 2, the margins of plate 21 overlap the margins of the aperture 18of wall 13 and the plate closely fits against the inner side of wall 13to tightly close such wall aperture. The lower end of plate 21, however,being free, may be flexed away from the wall 13 as will later appear.

Plate 19 normally abuts the face of plate 21 adjacent wall 13 and issecured to plate 21 at a place spaced from the plate apertures 22 in adirection toward the lower, or free end of plate 21. At the presenttime, rivets 26 pass through aligned apertures in respective plates 19,21 to eifect such securement. However, it will readily be apparent thatspot welding or the like could be employed for this purpose if desired.The importance of securing the plates 19, 21 together at the placedescribed will hereinafter be disclosed.

With the parts assembled as shown in FIGURE 2, element 14 will be in itsnormal position wherein it is disposed adjacent the lower wall It of theoven. When the oven is to be cleaned, it is only necessary to grasp theelement portion adjacent the oven door and swing the element up aboutits mounting and away from the lower oven wall 11) to the position seenin FIGURE 4. This it will be evident, will provide adequate space forcleaning the portions of wall 10 underlying the heating element. Notethat as the element is tilted to the position seen in FIGURE 4, plate 21will flex, its lower free end swinging away from the wall while theupper margin of plate 19 tilts away from the plate 21. The apertures 22in the plate 21, being larger than the portions of the element whichpass therethrough, do not interfere with the aforesaid relative'tiltingof the plates. Release of the element will cause the parts to return tothe position seen in FIGURE 2. The solid connections between the plate211 and oven wall 13, and between the plates 19 and 21, insure of goodearthing of the heating element 1 in any position of the latter.

As earlier indicated, an important feature of the present invention isthe place of securement between the plates i9, 21. With the plates thussecured together, plate 2.1 flexes over a relatively large span to thusmain tain the stresses induced by such fiexure wall within the elasticlimit of the material of which the plate is made. Obviously, if thestresses produced in the plate 21 by tilting of the element exceed theelastic limit of the plate material, as would be the tendency in priorunits now in use, the plate will be permanently deformed and will notreturn to the position seen in FIGURE 2 upon release of the element.

While only the lower, or baking, element has been illustrated herein, itwill be apparent that the same construction can as well be applied to anupper, or broiling, element merely by inverting the describedconstruction so that the element swings downwardly for cleaning insteadof upwardly. in such case suitable means, as a latch for example, willbe used to hold the element in its upper position. While two elementends 1.? pass through the plates 19, 21 in the construction illustrated,the construction could well be modified by providing but oneelement-passing aperture in the plates for accommodating but a singleelement end.

In view of the foregoing it will be apparent to those skilled in the artthat l have accomplished at least the principal object of my inventionand it will also be apparent to those skilled in the art that theembodiment herein described may be variously changed and modified,without departing from the spirit of the invention, and that theinvention is capable of uses and has advantages not herein specificallydescribed; hence it will be appreciated that the herein disclosedembodiment is illustrative only, and that my invention is not limitedthereto.

1 claim:

ii. In an electric heater assembly for use with an apertured wall, thecombination of an electric heating element extending through the wallaperture to dispose a heatgenerating portion of said element on one sideof said wall and a terminal portion of said element on the other side ofsaid wall, a first flat plate of resilient sheet metal larger than saidwall aperture and disposed on one side of said wall with its marginsoverlapping the margins of said aperture to close the latter, such platebeing apertured in register with said wall aperture, the plate aper-Lure-being larger than said element to freely pass the same, a pordon ofsuch plate adjacent one side of said wall aperture being anchored tosaid wall and the opposite portion of such plate being free to shifttoward and away from said one wall side upon plate fiexure, and a secondfiat plate, smaller than said wall aperture and secured to and extendingradially of said element, said second plate being secured fiatwise tothat face of said first plate adjacent said wall and at a place spacedfrom the aperture in said first plate in a direction toward saidopposite, free portion of the latter to minimize stress on said firstplate upon flexure thereof caused by tilting of said element.

2. An electric heater assembly for attachment to an apertured oven wall,comprising a large and a small metal plate in face to face relation, thelarger plate being of flexible material and said plates having certainmarginal portions adjoining and mechanically and electrically connectedand opposite free portions overlying and capable of moving apart throughexure of said large plate, a sieathed electric heating element having aterminal portion which is mechanically and electrically connected tosaid small plate and which passes through an oversize opening in saidlarge plate to accommodate free flexure of the latter, the free end ofsaid large plate being adapted to be mechanically and electricallyconnected to said oven wall at said oven aperture whereby said largeplate normally overlies the inner surface of said oven wall and closessaid oven aperture.

3. The construction according to claim 2 wherein the oven aperture andthe large and small plates are rectangular, said plates havingcorresponding long marginal portions adjoining and connected.

4. An oven assembly, comprising an oven having a rear wall formed withan aperture therein, a flexible flat metal plate having one marginalportion mechanically and electrically connected to said oven wail, saidplate being of larger size than said oven aperture to overlie and closethe same, a sheathed electrical heating element having terminal ends inside-by-side relation, and a rigid flat metal plate disposed fiatwiseagainst said flexible plate and mechanically and electrically connectedto said terminal ends and spanning the latter to rigidly connect thesame, said rigid plate being of a smaller size than said oven apertureand having a marginal portion mechanically and electrically connected tothat marginal portion of said flexible plate which is opposite said onemarginal portion so as to be supported for liatwise swinging movement.

References Cited by the Examiner UNITED STATES PATENTS 2,910,570 10/59Bremer et al 219-463 2,918,560 12/59 Kruse 2l9-404 2,955,189 10/60 Fry219-463 RECHARD M. WOOD, Primary Examiner,

MAX L. LEVY, Examiner.

2. AN ELECTRIC HEATER ASSEMBLY FOR ATTACHMENT TO AN APERTURED OVEN WALL,COMPRISING A LARGE AND A SMALL METAL PLATE IN FACE TO FACE RELATIN, THELARGER PLATE BEING OF FLEXIBLE MATERIAL AND SAID PLATES HAVING CERTAINMARGINAL PORTIONS ADJOINING AND MECHANICALLY AND ELECTRICALLY CONNECTEDAND OPPOSITE FREE PORTIONS OVERLYING AND CAPABLE OF MOVING APART THROUGHFLEXURE OF SAID LARGE PLATE, A SHEATHED ELECTRIC HEATING ELEMENT HAVINGA TERMINAL PORTION WHICH IS MECHANICALLY AND ELECTRICALLY CONNECTED TOSAID SMALL PLATE AND WHICH PASSES THROUGH AN OVERSIZE OPENING IN SAIDLARGE PLATE TO ACCOMMODATE FREE FLEXURE OF THE LATTER, THE FREE END OFSAID LARGE PLATE BEING ADAPTED TO BE MECHANICALLY AND ELECTRICALLYCONNECTED TO SAID OVEN WALL AT SAID OVEN APERTURE WHEREBY SAID LARGEPLAT NORMALLY OVERLIES THE INNER SURFACE OF SAID OVEN WALL AND CLOSESSAID OVEN APERTURE.